Adjustable floor receptacle mount

ABSTRACT

An adjustable floor receptacle mount is provided that includes a housing movable within a stationary casing fitted into a circular opening in a concrete floor. The housing and the casing are each formed of a pair of interlocking extruded channel structures whose walls are shaped to facilitate the installation and operation of the floor receptacle mount. In order to simplify the withdrawing of the housing from a recessed position within the casing, a cap provided on a cover plate for the housing and operating in conjunction with a latching mechanism pops up when the housing is unlatched. The cap thus provides a convenient handle by which the housing can be quickly pulled out of the casing in the floor when it is desired to use the electrical service provided by the receptacles on the sides of the housing.

ited States tent Cole Feb. 29, 1972 [54] ADJUSTABLE FLOOR RECEPTACLEMOUNT Primary Examiner-William T. Dixson, Jr.

Assistant Examiner-James R. Garrett [72] Inventor: Stephen W. Cole,Altadena, Calif. Anomey |ohn M tl [:3] :slsignee: W.2(lIolle9:0Co.,Inc., El Monte, Calif. 7 1 ABSTRACT 2 d: 1 l e ug An adjustable floorreceptacle mount is provided that includes PP 78 a housing movablewithin a stationary casing fitted into a circular opening in a concretefloor. The housing and the casing are each formed of a pair ofinterlocking extruded channel [52] U.S. Cl Nd/57, stmctures whose wallsare shaped to facilimm the installation [51] Int Cl 6 and operation ofthe floor receptacle mount. In order to sim- [58] Fie'ld 4 3 5 3 plifythe withdrawing of the housing from a recessed position i within thecasing, a cap provided on a cover plate for the housing and operating inconjunction with a latching mechanism pops up when the housing isunlatched. The cap thus provides [56] References Cited a convenienthandle by which the housing can be quickly UNITED STATES PATENTS pulledout of the casing in the floor when it is desired to use the electricalservice provided by the receptacles on the sides 2,811,574 10/1957Guerrero ....174/57 fth housing 2,811,575 10/1957 Guerrero ....174/573,433,886 3/1969 Myers ..174/57 10 Claims, 9 Drawing Figures PatentedFeb. 29, 1972 3,646,244

3 Sheets-Sheet 2 I N VE/V Toe STEPA/E/V W C045 yalwydfa Patented Feb.29, 1972 3 Sheets-Sheet 5 INVEN roe. STEP/, E/VII I C045 ADJUSTABLEFLOOR RECEPTACLE MOUNT This invention relates to adjustable floorreceptacle mounts and more particularly to a novel structure for such amount.

It is highly desirable to provide a movable housing in a floorreceptacle mount that can be either lowered within a stationary casingprovidedin the floor and latched in a hidden position therein flush withthe surrounding floor area or that can be easily lifted out of thecasing and held in a withdrawn position above the level of the floor inwhich position the electrical receptacles on the sides of the housingare readily available for providing service to electrical equipment.

It can be readily appreciated that when it is desirable to provide suchan adjustable floor receptacle mount that extends through an openingprovided in a concrete floor, it simplifies and reduces the expense ofthe labor of installation thereof if the recess or opening to be boredin the concrete floor is of a circular configuration. This, however,requires that the casing for the mount to be placed in this circularopening be of a circular configuration. It is also appreciated that inorder to latch the housing when it is in its hidden position within thecasing or to unlatch the housing so that it can be lifted therefrom whenit is desired to use the services provided by the receptacles, it is ofadvantage to apply a rotative force in some manner to the housing.However, this rotative force is of no effect unless the surface of thecasing in which the housing vertically slides is shaped so as to resistsuch rotation.

Accordingly, in order to provide shapes for the casing and housing of anadjustable floor receptacle mount which will accommodate these and otherrequirements without having to machine or specially fabricate the parts,the present invention provides for forming the casing and housing ofextruded open channel structures that can be readily manufactured in acontinuous manner. The extruded open channel structures are so shapedthat two separate lengths of the identically shaped structures can beinterlocked or mated together by sliding the side edge portions thereoflengthwise within each other to form a hollow closed cross-sectionalunit. Thus, the casing is formed of two lengths of interlockedidentically shaped channel structures such that although the crosssection of its wall configuration is generally circular, its interiorwall configuration is formed with flat surfaces on diametrically opposedportions thereof. The housing is likewise formed of two lengths ofinterlocked identically shaped open channel structures such thatalthough the cross section thereof is generally square, the corner wallsthereof are rounded to conform with a close sliding fit within thecircular wall of the casing. Thus, the rounded corners of the housingare permitted to slide vertically along the circular interior wall ofthe casing while the flat sides of the housing abutting the flatsurfaces on diametrically opposed portions of the interior wall of thecasing restrain the housing from rotation therein. It should be notedthat by forming the casing and housing of extruded structures otheruseful shapes can be readily provided which will facilitate theinstallation and operation of such adjustable floor receptacle mounts.

When a floor receptacle mount is residing with its housing in its hiddenposition within the casing in the floor, a cover plate on the upper endof the housing is positioned flush with the level of the floor andlatched tightly against a trim ring attached to the stationary casingsuch as to seal the mount. Because the cover plate is flush with thefloor with no protruding parts, there is no way of grasping hold of thecover plate after being unlatched in order to lift the housing out ofthe floor without using a special tool to pry or otherwise lift up thecover plate. Thus, it is highly desirable to provide a built-in deviceon the mount for being able to simply lift the housing after it isunlatched such that it can be withdrawn from the casing when serviceconnections are to be made to the receptacle thereon, and then loweredback into the casing when the service connections are no longerrequired.

The adjustable floor receptacle mount of the present invention providesa cap on a bolt extending through the center of the cover plate for thehousing which operates in conjunction with its latching mechanism suchthat the cap pops up above the level of the cover plate when the housingis unlatched. The cap thus provides a convenient handle by which thehousing can be quickly pulled out of the casing in the floor.

Accordingly, the broad object of the present invention is to provideimprovements in the construction of adjustable floor receptacle mounts.

Another object of the present invention is to provide an improvedstructure for such a mount by manufacturing both the stationary casingand the movable housing therefor out of extruded channel structures.

Another object of this invention is to provide a novel popup deviceoperating in conjunction with a latching mechanism for facilitating thelifting of the housing of the floor mount when it is in its hiddenposition in the casing flush with the level of the floor.

The manner in which the above objects are accomplished in accordancewith the invention, as well as other objects, advantages and featuresthereof, will become apparent from the following description and theaccompanying drawings wherein:

FIG. 1 is a top plan view of the floor receptacle mount of the presentinvention shown with the movable housing in its hidden position flushwith the level of the floor;

FIG. 2 is a vertical sectional view of the floor receptacle mountshowing the casing with the movable housing in its hidden positiontherein flush with the level of the floor;

FIG. 3 is a perspective view of the floor receptacle mount shown withthe movable housing in its withdrawn position above the level of thefloor;

FIG. 4 is a vertical sectional view of the floor receptacle mountshowing the casing with the movable housing in its withdrawn positiontherein so as to extend above the level of the floor;

FIG. 5 is a perspective view showing the details of the trim ring asviewed from below the floor level;

FIG. 6 is a plan and partially horizontal sectional view of the mounttaken generally at different levels along line 6-6 of FIG. 2;

FIG. 7 is a perspective view showing the details of the cover plateassembly for the housing;

FIG. 8 is a horizontal sectional view of the mount taken along line 88of FIG. 2 and showing the latching mechanism in its latched andunlatched positions; and

FIG. 9 is a horizontal sectional view of the mount taken along line 99of FIG. 2 and showing the spring supported stop for holding the housingin its withdrawn position.

Like referenced numerals correspond to like elements throughout thefigures of the drawings.

Referring to the drawings, the adjustable floor receptacle mount of thepresent invention includes an inner housing denoted by referencecharacter 10 and an outer casing denoted by reference character 16. Thehousing 10 is movable within casing 16 which is stationarily held in acircular opening 35 provided in a concrete floor. In FIGS. 1 and 2 themovable housing 10 is illustrated in its recessed or hidden positionwithin casing 16 in which it is flush with the level of the floor. InFIGS. 3 and 4 the movable housing 10 is illustrated in its withdrawn orin-use position in which the upper half thereof is pulled out of thecasing 16 and extends above the level of the floor.

Housing 10, which is generally square in cross section, is formed of twoidentically shaped lengths of aluminum extrusions 11 and 12 the sides ofwhich are interlocked at 13 and 14 by sliding the projections on theside end portions thereof within each other to form a hollow closedcross-sectional unit, as shown in FIGS. 6, 8 and 9. More specifically,as shown at 13 in FIG. 6, a side projection 11d of extrusion 11 is slidlengthwise into the opening of a side end projection 12d of extrusion12. The corners, such as 11f, of the housing 10 are rounded such thatthe housing is slidably mounted within the generally circular stationarycasing 16 which is likewise formed of two identically shaped lengths ofaluminum extrusions 17 and 18 the side edges of which are interlocked at20 and 21, similarly to the extrusions of housing 10, as shown in FIGS.6, 8 and 9. The identical extrusions 17 and 18 forming casing 16 providerespective flat surfaces 170 and 18a on diametrically opposite sides ofthe internal wall thereof which together with respective shoulders 18band 17b provide for mating with the respective opposing flat sidewalls12a and 11a of the identical extrusions 12 and 11 forming movablehousing 10.

The housing is provided with a top circular cover plate 22 which has abridge member 24 secured to the underside thereof by welding, forexample, as shown in FIG. 7. The ends of bridge member 24 extenddownwardly and inwardly to form brackets 26a and 26b. The cover plate 22is securely attached to the upper end of housing 10 by mounting screws28a and 28b extending through the flat back and front walls 110 and 120,respectively, of housing 10 and the downwardly extended portions ofbrackets 26a, 26b of bridge member 24. The inwardly extending portionsof brackets 26a and 26b have a horizontal barrier 32 attached thereto bymounting screws 32a and 32b. The horizontal barrier 32 serves to shieldreceptacles 19 mounted within the housing 10 from dirt, water or otherforeign matter. The periphery of cover plate 22 projecting beyond thesides of the inner housing 10 is provided on the underside thereof witha peripheral gasket 25 (FIG. 2). A bottom circular cover plate 30provided with a sealing gasket 31 is secured onto the bottom end ofhousing 10 by mounting screws 33.

The flat back and front walls 11c and 120, respectively, of housing 10are provided with rectangular openings 38 (FIG. 2) to accommodate theelectrical receptacles 19 on a pair of panels which are attached tothese walls by mounting screws 15a. It should be understood that avariety of replaceable panels 15 formed to accommodate a variety ofelectrical receptacles 19 can be provided for attachment to the frontand back walls of housing 10 in the aforementioned manner. As indicatedin FIG. 9, a vertical barrier 68 may be inserted in grooves 12b and 11bformed on the respective flat sidewalls 12a and 11a of housing 10 whenit is desirable to have the mount provided with electrical devices orreceptacles 19 of high and low potential requirements.

The stationary casing 16 is formed with four radially extending ribs17c, 17d, 18c and 18d equally spaced about the outer circular wallthereof for facilitating the positioning of casing 16 into the circularopening 35 provided in the concrete floor. As shown in FIGS. 2 and 6, atrim ring 37, preferably formed of a stamping, is positioned over theopening 35 in the floor with its outer periphery forming a circular rim23 extending over the edge thereof and with its inner periphery steppeddownwardly to form an inner flange 27. Flange 27 is formed with sideportions positioned over the interlocking end portions and 21 of theouter casing 16 so as to be held thereon by mounting screws 20a and 21a.A sealing gasket 38a is positioned under circular rim 23.

It should thus be understood that casing 16 is positioned in opening 35provided in the concrete floor and supported therein by the trim ring 37which has its inner flange 27 attached to the upper end of outer casing16 and its outer rim 23 extending about the circular edge of opening 35.Outer rim 23 sits above the surface of the concrete floor such that itsupper surface matches the level of the tile 34, for example. The lowerportion of casing 16 extending below the lower surface of the concretefloor is provided with a sleeve 40 that can be vertically positionedalong the lower end portion of casing 16 such that its upper flange 41contacts the lower surface of the concrete floor. Screws 42 passingthrough sleeve 40 engage threaded openings in the interlocking wallportions of the casing 16 (FIG. 9) to hold the sleeve 40 in thisposition.

As shown in FIG. 2, it is contemplated that the space surrounding theportion of the floor receptacle mount located below the concrete flooris enclosed by a metal box 46 which is attached to the undersurface ofthe floor by screws 48. The inside surface of box 46 is lined with anasbestos insulation, for example, so as to serve as a heat barrier forthe floor mount. A

connector 61 attached to a central opening in the bottom cover 30provides for holding flexible cable 63 such that its ends can extendupwardly within housing 10 and be connected (not shown) to theelectrical receptacles 19 held on the side panels 15 of housing 10. Theother end of cable 63 is attached by connector 66 on the wall of box 46to an outlet box 64.

It should now be clear that the movable housing 10 with the cover plate22 attached on the upper end thereof can slide vertically within thestationary casing 16 to either its hidden position flush with the levelof the floor as illustrated by FIGS. 1 and 2 or to its withdrawnposition above the level of the floor as illustrated by FIGS. 3 and 4.In a manner to be described in the ensuing description, when the housing10 is latched in its hidden position the outer periphery of cover plate22 is sealed by gasket 25 compressingly engaged against flange 27 oftrim ring 37 and when the housing 10 is held in its withdrawn positionthe outer portion of bottom cover 30 is sealed by gasket 31 which abutsup against the lower end of casing 16.

The housing 10 is held in its withdrawn position by a pair of springsupported stops 45a and 45b which are positioned intermediately withinthe housing 10 on opposite walls 12a and 11a thereof with the lower endsof the spring supports 43a and 43b held by screws 44a and 44b. The stops45a and 45b extend through respective openings 39a and 39b provided onthe opposite sidewalls 12a and 11a of the housing 10 into the recessesprovided between the circular wall of the casing 16 and the sidewalls ofthe housing 10, as shown in FIG. 9. Stops 45a and 45b are provided withslanted surfaces such that as the housing 10 is raised past the innerflange 27, the stops 45a and 45b are deflected inwardly. Then, upon thehousing 10 reaching its withdrawn position the stops 45a and 45b snapback out through openings 39a and 39b so as to rest against the uppersurface of inner flange 27.

Mounted on the cover plate 22 and within the upper portion of innerhousing 10 is a mechanism which is used for latching housing 10 to thecasing 16 when it is in its recessed position within the casing 16. Thismechanism also operates to facilitate the lifting of the housing 10 outof its recessed position. To this end, cover plate 22 is formed with acircular well 29 in the center thereof which seats cap having a slot 53.Cap 50 forms the head of a bolt 51 whose threaded body passes through acentral clearance opening 52 provided in the center of cover plate 22. Aspring 54 positioned between the underside of cap 50 and the uppersurface of the well 29 on cover plate 22 tends to urge the bolt 51 in anupward position (FIG. 4). A horizontally disposed latch member 55provided with latching end portions 57a and 57b is provided with athreaded opening 58 in the center thereof for receiving the threadedbody of bolt 51. A nut 59 is provided on the lower end of the body ofbolt 51. A spring 60, positioned between the nut 59 and the lowersurface of latch member 55, takes up any slack in the threads so as tourge the latch member 55 into an upward position such that it tends tomove with the rotation of bolt 51 until it meets a resistance. As shownin FIGS. 2, 6 and 8, when the cap 50 is forced down against the spring54, the latch member 55 is lowered such that its end portions 57a and57b can be rotated in a clockwise direction into horizontally disposedslots 62a and 62b respectively provided on the opposite sidewalls 12aand 11a of inner housing 10. Upon being rotated about 45, the endportions 57a and 57b, respectively, bear against the surfaces 17f and18f of the interlocking end portions 21 and 20 of the casing 16. Furthertightening of the cap 50 in a clockwise direction then causes threadedbolt 51 to draw up on the latch member 55 such that the end portions 57aand 57b thereof bear upwardly against the depending inner shoulders 65aand 65b provided on diametrically opposing sides of inner flange 27 ofthe trim ring 37. This compresses the gasket 25 provided on theperiphery of the cover plate 22 so as to seal the floor receptaclehousing 10 in its recessed position within the casing 16.

When the floor receptacle housing 10 is to be withdrawn from the casing16 to its in-use position above the concrete floor, the cap 50 isrotated in a counterclockwise direction by turning a coin or a similarlyshaped object positioned in the slot 53. The initial turning of the cap50 provides for loosening the latch member 55. As shown in FIGS. 4 and7, upon further rotation in this direction, the latch member-55 rotateswith the bolt 51 because of the force of spring 60 until the respectiveend portions 57a and 57b of the latch member 55 clear the horizontallydisposed slots 62a and 62b in the opposite sidewalls 12a and 11a ofhousing 10, and moves to the position shown in H6. 8, in which the endportions 57a and 57b respectively contact the flat front and back walls12c and llc of the housing. The nut 59 on the lower end of the bolt 51prevents the bolt from inadvertently being rotated out of latch member55. Latch member 55 is now free to move upwardly by the force of spring54 such that the bolt 51 and cap 50 pop up, as shown in FIG. 4, so as toprovide a convenient handle for lifting the housing out of the casing16.

As described previously, the housing 10 is lifted until gasket 31 onbottom cover plate 30 bears against the bottom end of casing 16 at whichtime the spring-supported stops 45a and 45b snap out into flange 27 tosupport the housing 10 in its withdrawn position. When it is desired toagain position the housing into its recessed position in the floor, thestops 45a and 45b can be pressed inwardly and the housing 10 is thenlowered down into the casing 16 while being held by cap 50. The cap 50is then pressed down against spring 54 which lowers the latch member 55such that rotating the cap 50 in a clockwise direction by inserting acoin in its slot 53 will rotate the latch member 55 approximately 45until arrested by the end portions 570 and 57b thereof respectivelycontacting the inner locking portions 20 and 21 of the casing 16 (FIGS.6 and 8). When in this position the end portions 57a and 57b of thelatch member are below the depending shoulders 65a, 65b on inner flange27 of the trim ring 37. Thus, continued tightening of cap 50 in aclockwise direction causes the end portions of the latch member 55 tobear upwardly against the inner shoulder 65a and 65b of the trim ring37. This causes the periphery of the cover 22 to bear down on the gasket25 so as to seal the mount while in its recessed position.

Although the description herein has been concerned with a particularlyillustrative embodiment, it is to be understood that the invention issubject to various modifications in both the construction ad arrangementthereof without departing from the spirit of the invention. Theinvention, therefore, should be considered as including all possiblemodifications and variations coming within the scope of the invention asdefined in the appended claims.

What is claimed is:

1. An adjustable floor receptacle mount comprising a casing adapted tobe stationarily positioned in a circular opening in the floor of abuilding, a trim ring having an inner flange with depending shouldersand being attached to the upper end of said casing, a housing mated forsliding movement within said casing, said housing being provided withreceptacles on the vertical sidewalls thereof, a circular cover plateattached to the upper end ofsaid housing, a bolt having a cap on theupper end thereof and a threaded body extending downwardly through anopening in the center of said cover plate, a spring beneath the cap ofsaid bolt for urging said bolt in an upward direction, and a latchingmeans threadably engaged to the body of said bolt, whereby when saidbolt is depressed down against the action of said spring and is rotatedin one direction the latching means bears upwardly against the shoulderson the flange of said trim ring so as to latch said housing within saidcasing in a recessed position in which said cover plate is flush withthe floor, and whereby when said bolt is rotated in the other directionthe latching means is freed of said trim ring shoulders and the bolt'islifted up by the action of said spring such that the cap on the upperend thereof can be used as a 1 handle to raise the housing out of thecasing to a withdrawn position in which the receptacles on the saidsidewalls thereof are exposed for use above the floor.

2. The invention in accordance with claim 1 wherein said housing andsaid casing are each formed of a pair of identically shaped lengths ofextrusions which are interlocked at the side edges thereof.

3. The invention in accordance with claim 2 wherein the housing formedby said interlocked identically shaped lengths of extrusions has agenerally square cross section with rounded corners, and the casingformed by said interlocked identically shaped lengths of extrusions hasa generally circular cross section with flat portions on diametricallyopposite inside surfaces thereof, and wherein said housing is mated toslide within said casing with the rounded corners thereof engaging thecircular inside wall of said casing and with the flat sides thereofengaging the flat portions on the inside wall of said casing.

4. The invention in accordance with claim 1 wherein said circular coverplate is provided with a peripheral gasket on the underside thereofwhich bears against the flange of said trim ring when said housing islatched to said casing by said latching means.

5. The invention in accordance with claim 4 wherein said latching meanscomprises a transverse latching member with a threaded opening in thecenter thereof for receiving the threaded body of said bolt, and whereinsaid housing is provided with transverse slots on opposite sidewallsthereof into which the ends of said transverse latching member can berotated so as to engage the lower end of the flange shoulders of saidtrim ring for latching said housing to said casing.

6. The invention in accordance with claim 3 wherein the outer circularwall of said casing is provided with a plurality of spacedlongitudinally extending ribs to facilitate the installation of saidcasing in the circular opening of the floor.

7. The invention in accordance with claim 1 wherein the housing isprovided with a pair of spring-supported stops extending throughopenings in the opposite sidewalls thereof, and wherein said stopsproject out of said housing onto the upper surface of the flange of saidtrim ring to hold said housing when in its withdrawn position above thefloor.

8. The invention in accordance with claim 5 including an additionalspring on the body of said bolt urging said latching member in an upwarddirection, whereby when said bolt is depressed down against the actionof said spring and is initially rotated in one direction the latchingmember is rotated with the bolt to a position below the flange shouldersof said trim ring, and whereby further rotation of said bolt draws thecircular cover plate down on the flange of said trim ring such that theperipheral gasket compressingly seals the cover plate.

9. In an adjustable floor receptacle mount, the combination comprising acasing stationarily positioned in an opening in a floor, a housingprovided with electrical receptacles on the vertical sidewalls thereof,a cover plate secured to the upper end of said housing, said housingbeing shaped to have a sliding movement within said casing to a recessedposition in which said cover plate is flush with the level of the floorand a withdrawn position in which the receptacles thereon are exposedfor use above the floor, latching means for latching said housing in itsrecessed position within said casing, and a cap located on the center ofsaid cover plate, said cap being supported so as to be urged into anupward position above the cover plate when said housing is not latchedto said casing by said latching means whereby said cap can be used towithdraw said housing from said casing.

10. In an adjustable floor receptacle mount, the combination comprisinga casing formed of a pair of identically shaped lengths of extrusionswhich are interlocked along the side edges thereof, said casing having agenerally circular cross section with flat portions on diametricallyopposite inside surfaces thereof, a trim ring attached to the upper endof said casing, said casing being adapted to be stationarily positionedin a circular opening in the floor of a building with the trim ringprojecting over the rim of said opening, a housing formed of a pair ofidentically shaped lengths of extrusions which are interlocked along theside edges thereof, said housing having a generally square cross sectionwith rounded corners, a circular cover plate attached to the upper endof said housing, said between a recessed position in which said coverplate is flush with the level of the floor and a withdrawn position inwhich the receptacle devices thereon are exposed for use above thefloor.

1. An adjustable floor receptacle mount comprising a casing adapted tobe stationarily positioned in a circular opening in the floor of abuilding, a trim ring having an inner flange with depending shouldersand being attached to the upper end of said casing, a housing mated forsliding movement within said casing, said housing being provided withreceptacles on the vertical sidewalls thereof, a circular cover plateattached to the upper end of said housing, a bolt having a cap on theupper end thereof and a threaded body extending downwardly through anopening in the center of said cover plate, a spring beneath the cap ofsaid bolt for urging said bolt in an upward direction, and a latchingmeans threadably engaged to the body of said bolt, whereby when saidbolt is depressed down against the action of said spring and is rotatedin one direction the latching means bears upwardly against the shoulderson the flange of said trim ring so as to latch said housing within saidcasing in a recessed position in which said cover plate is flush withthe floor, and whereby when said bolt is rotated in the other directionthe latching means is freed of said trim ring shoulders and the bolt islifted up by the action of said spring such that the cap on the upperend thereof can be used as a handle to raise the housing out of thecasing to a withdrawn position in which the receptacles on the saidsidewalls thereof are exposed for use above the floor.
 2. The inventionin accordance with claim 1 wherein said housing and said casing are eachformed of a pair of identically shaped lengths of extrusions which areinterlocked at the side edges thereof.
 3. The invention in accordancewith claim 2 wherein the housing formed by said interlocked identicallyshaped lengths of extrusions has a generally square cross section withrounded corners, and the casing formed by said interlocked identicallyshaped lengths of extrusions has a generally circular cross section withflat portions on diametrically opposite inside surfaces thereof, andwherein said housing is mated to slide within said casing with therounded corners thereof engaging the circular inside wall of said casingand with the flat sides thereof engaging the flat portions on the insidewall of said casing.
 4. The invention in accordance with claim 1 whereinsaid circular cover plate is provided with a peripheral gasket on theunderside thereof which bears against the flange of said trim ring whensaid housing is latched to said casing by said latching means.
 5. Theinvention in accordance with claim 4 wherein said latching meanscomprises a transverse latching member with a threaded opening in thecenter thereof for receiving the threaded body of said bolt, and whereinsaid housing is provided with transverse slots on opposite sidewallsthereof into which the ends of said transverse latching member can berotated so as to engage the lower end of the flange shoulders of saidtrim ring for latching said housing to said casing.
 6. The invention inaccordance with claim 3 wherein the outer circular wall of said casingis provided with a plurality of spaced longitudinally extending ribs tofacilitate the installation of said casing in the circular opening ofthe floor.
 7. The invention in accordance with claim 1 wherein thehousing is provided with a pair of spring-supported stops extendingthrough openings in the opposite sidewalls thereof, and wherein saidstops project out of said housing onto the upper surface of the flangeof said trim ring to hold said housing when in its withdrawn positionabove the floor.
 8. The invention in accordance with claim 5 includingan additional spring on the body of said bolt urging said latchingmember in an upward direction, whereby when said bolt is depressed downagainst the action of said spring and is initially rotated in onedirection the latching member is rotated with the bolt to a positionbelow the flange shoulders of said trim ring, and whereby furtherrotation of said bolt draws the circular cover plate down on the flangeof said trim ring such that the peripheral gasket compressingly sealsthe cover plate.
 9. In an adjustable floor receptacle mount, thecombination comprising a casing stationarily positioned in an opening ina floor, a housing provided with electrical receptacles on the verticalsidewalls thereof, a cover plate secured to the upper end of saidhousing, said housing being shaped to have a sliding movement withinsaid casing to a recessed position in which said cover plate is flushwith the level of the floor and a withdrawn position in which thereceptacles thereon are exposed for use above the floor, latching meansfor latching said housing in its recessed position within said casing,and a cap located on the center of said cover plate, said cap beingsupported so as to be urged into an upward position above the coverplate when said housing is not latched to said casing by said latchingmeans whereby said cap can be used to withdraw said housing from saidcasing.
 10. In an adjustable floor receptacle mount, the combinationcomprising a casing formed of a pair of identically shaped lengths ofextrusions which are interlocked along the side edges thereof, saidcasing having a generally circular cross section with flat portions ondiametrically opposite inside surfaces thereof, a trim ring attached tothe upper end of said casing, said casing being adapted to bestationarily positioned in a circular opening in the floor of a buildingwith the trim ring projecting over the rim of said opening, a housingformed of a pair of identically shaped lengths of extrusions which areinterlocked along the side edges thereof, said housing having agenerally square cross section with rounded corners, a circular coverplate attached to the upper end of said housing, said housing beingmated to slide within said casing with the rounded corners thereofengaging the circular inside surfaces of said casing and with oppositesides thereof engaging the flat portions on the diametrically oppositeinside surfaces of said casing, and receptacle devices mounted on thevertical walls of said housing, said housing being slidable within Saidcasing between a recessed position in which said cover plate is flushwith the level of the floor and a withdrawn position in which thereceptacle devices thereon are exposed for use above the floor.